Recoil-operated firearm.



o. B. SAALHELD.

RECOIL OPERATED FIREARM.

2 SHEETS-SHEET I Patented June 5, 1917 APPLICATIQN FILED AUG- 8,1916.

UNITED STATES PATENT' OFFICE.

OLIVERBERRY SAALFIELD, 0F WEST HOBOKEN, NEW JERSEY, ASSIGNOR TO MAXIM MUN'ITIONS CORPORATION', 0F NEW YORK, N. Y., A CORPORATION OF DELAWARE.

RECOIL-OPERATED FIREARM.

Specication of Letters Patent.

Patented June 5, 1917.

Application led August 8, 1916. Serial No. 113,808.

. FmLD, a citizen of the United States, residing at West Hoboken, in the county of Hudsony and State of New Jersey, have invented certa-in new and useful Improvements in Recoil-Operated Firearms, of which the following is a speciication.

This invention relates to magazine firearms, and more especially to a novel improvement in automatic shoulder rifles of the recoil-operated type.

Primarily the invention contemplates a riiie of this character having a minimum amount of recoil, and capable of belng fired rapidly from the shoulder without unduly deranging the aim of the rer. That is to say, the invention has in view a rifle employing novel instrumentalities which not only absorb the impact of the recoil to a certain extent, thereby enabling the iirer to hold the gun steady, but which also utilize the recoil to readjust the mechanism to recock the gun for ring the next shot, and to automatically eject the ired cartridge.

Another object of the invention is to provide a novel construction and arrangement for feeding the cartridges from the magazine into the firing chamber of the gun barrel by means of a spring-actuated breech assembly, which is s'o arranged with relation to the breech end of the gun barrel, that in its forward movement to position the eartridge therein, it automatically becomes locked with the barrel and detonates the cartridge, and at the same time unlocks the barrel so that the lat-terA will be free to be acted upn by the recoil.

A further object of the invention is to provide a gun that will remain reasonably cool during rapid iire, and with this end in view, the invention proposes to provide a novel and practical cooling means to keep the temperature of the gun barrel within reasonable limits.

`With the above and other objects in view which will more readily yappeal' as the nature of the invention is better understood, the same consists in the novel construction, combination and arrangement of parts hereinafter more fully described. illustrated and claimed.

A preferred and practical embodiment of the invention is illustrated in the accompanying drawings, in which- Figure 1 is a top vplan View of the improved firearm.

Fig. 2 is a vertical sectional view thereof with the mechanism cocked.

Fig. 3 is an enlargeddetail sectional view of the breech end of the gun showing the relative position of the several parts thereof when the recoil of the barrel has pushed lthe breech-boltI to its extreme backward p0- sition for engagement with the triggermechamsm.

Fig. 4 is an .enlarged horizontal sectional view showing the relative positions of the several parts shown in Fig. 3.

Fig. 5 is an enlarged vertical sectional view showing the breech-bolt in cocked position in full lines and the normal positlon of the barrel also in full lines, the dotted lines indicating the bolt interlocked with the barrel when the cartridge is detonated.

Fig. 6 is an enlarged detail sectional view of the breech-bolt carrier showing more clearly the breech-bolt, and how the same is locked in extended lposition when the gun parts are in normal position.

bolt.

Fig. S is an enlarged detail view partly in section of the spring attaching clip used in connection with the barrel-returning spring.

Fig. 9 is an end elevation of the clip shown in Fig. 8.

Similar reference characters designate corresponding parts throughout the several figures of the drawings.

As previously indicated, the present invention has in view a recoil operated gun, wherein the breech-bolt and the gun barrel are normally spaced apart, so that a cartridge from the magazine will normally lie in the feeding zone between these two elements. Upon the release of the spring-actuated breech-bolt, the same moves forward toward the relatively fixed gun barrel to place the cartridge therein and in its forward flight. the breech bolt is caused to become interlocked with the gun barrel substantiall)v simultaneously with the unlockinghofthe latter fromits relative fixed po- Fig. 7 is a detail plan view'of the breechsition and the detonation of the cartridge, whereupon the recoil from the explosion will cause both barrel and breech-bolt. to move backward to again recock the gun. Afterv the interlocked parts have reached their backward limit of movement, the breech-bolt is held in place by the sear of the trigger device, and the barrel moves forward to its relatively fixed firing position to thus eject the fired cartridge and to be reset and relocked in firing position.

Accordingly, in carrying out the invention, it is proposed to employ a gun casing 1 having at one end thereof a breech casing 2, which are respectively mounted in the conventional manner on the forearm 3 and stock piece 4. The casing 1 is of relatively large diameter and may be provided adjacent its breech end with a plurality of air intake openings 5, and an interior abutment and guide collar 6 against which the gun .barrel 7 arranged within the casing may strike to limit its forward movement. The said gun barrel 7 is thus mounted to have a free sliding movement in the casing 1 through the guide 6, and has a relatively large air space or cooling jacket between the outer surface thereof and the interior of the casing to provide an air cooling chamber.

With further reference to the gun barrel 7, it will be observed that the muzzle end thereof terminates short of the mouth of the gun casing 1, so that when a cartridge is fired, the products 0f the explosion issuing from the muzzle of the barrel will create a' partial vacuum thereat and thus draw in cool air through the ports 5 and cool the gun barrel. The breech end of the gun barrel 7 is provided with a firing chamber 8 and a keeper yoke 9 fitted to the end of the barrel and having the opposite rearwardly projecting yoke-arms 9 provided with the inturned holding lugs 10. At an intermediate point, the barrel has adjustably fitted thereon an attaching clip 11 having a pivotally mounted arm 12 to which is connected one end of a barrel retracting spring 13, the other end of which is made fast to the forearm 3. As will be apparent from Figs. 2, 8, and 9 of the drawings, thevvarm 12 of the clip is provided with an upstanding lug 12a for engaging with a radial hole in the barrel, to maintain the correct relative position of the clipto the fixed point of the spring.

The upper part of the-breech casing 2 forms a continuation of the gun casing 1, while the lower part thereof constitutes a framework for supporting the magazine and trigger mechanism. The portion of the breech casing adjacent the forearm 3 is provided with a spring-pressed detent 14,^which has one face beveled as at 15 as clearly 'shown' in Figs. 2 and 5% of the drawings,

whereby cartridges'from the magazine may be assisted into the firing chamber 8 of the gun, while the flat side 16 of the head of the detent engages with the end of the barrel to hold the same in its relatively fixed firing position.

The portion of the breech-casing in which the breech mechanism B slides is also provided at its to side with a cartridge ejecting opening 1 arranged to one side of the central longitudinal axis of the casing to direct the empty shell away from the face of the firer. At its underside, the said breechcasing is provided with a relatively large slot or freeway 18 in which a portion of the breech bolt travels. One edge of this slot 18 is provided with a longitudinal fixed cam 19 for engaging with the device which holds the breech-bolt in locked position, to thereby release the same in the forward flight of the breech-bolt whereby the bolt and gun barrel may become interlocked as will hereinafter more fully appear.

Referring now to the breech-bolt device B, it will be observed that the same includes' a bolt carrier and breech-bolt fitted thereto. The breech-bolt carrier 20 is of substantially cylindrical formation and is provided at its lower side with a check shoulder 21 and a cocking shoulder 22 adapted to be engaged by the sear of the trigger mechanism as will presently appear. The body of the bolt carrier is also provided with a forwardly eX- tending detent engaging fork 23 clearly Shown in Fig. 2, and which travels in the slot 18 so that in the forward movement of the carrier 20, the same depresses the head of the detent 14 to thus unlock, at the proper 'and provided with the cap detonating point 28 at its other end, which latter may project into the recessed cartridge seat 29 of the lfiring bolt as clearly shown in Figs. 8 and 4.

The firing bolt 25 is provided on its periphery with a spiral slot 30, which receives a pin 31 inserted radially through the body of the bolt carrier, so that the movement of the bolt may be both rectilinear and rotary. The forward end of the bolt 25 is provided with the oppositely located locking projections 32 for engaging with the holding lugs 10 of the keeper yoke 9 when the breechbolt moves forward to position the cartridge in' the firing chamber of the barrel. One of the projections 32 may be provided with a circi'lmferential groove 33 .clearly shown in Figs. 5, 6, and 7 of the drawings for `engaging with the holding and guiding rib 33%? of a suitable bolt steadying element 34 which :is

'portion of the bolt carrier 20. The rear end of the firing bolt 25 is provided with a trans'- verse recess 35 which receives the lockin end 36 of a sprin pressed locking pawl 3 pivotally mounte between its ends lin the bolt carrier 20 as clearly` shown in Fig. 6 of the drawings. This locking, pawl 'is provided with an enlarged normally exposed terminal contact headv 38 at -one end for engaging with the cam 19 of the breech casing in the forward movement of the breech bolt carrier so that the breech or firing bolt 25 becomes unlocked.

In this connection, it may be noted that in its normal position, that is, the position the bolt assumes when the gun is cocked, the {iring bolt is extended, as shown in Figs. 2, 5, and 6 of the drawings. When the bolt is thus extended, or in other words, projects considerably forward from the end of the carrier, ,the locking end 36 of the detent 37 is in engagement with the transverse locking recess' 35. The purpose of havin the cartridge positioning bolt 25 locked 1s to displace the cartridge from the cartridge zone into the firing chamber of the barrel, and the initial movement of the bolt carrier, in its forward flight, displaces the cartridge from its position at the top of the cartridge compartment into practically its full position in the firing chamber.' At the instant the cartridge is pushed into the firing chamber, the portion 38 of the detent 37 engages the cam 19 and thus releases the end 36 of the detent from the recess 35 to permit the rotation of the bolt 25 due -to the push the firing pin through the bolt and det,V onate the cartridge held locked in the ring chamber by the breech-bolt which has become turned as above indicated. Then the recoil from the explosion of the cartridge causes the locked barrel and breech mechanism to move rearwardlyvtogether. This action becomes possible because the barrel has previously been 'unlocked by the engagement of the fork 23 with the detent 14, and causes the engagement of the breech-bolt with the trigger mechanism as will more fully apear. p With further reference to the' breech mechanism B, it will be observed that the same also includes a hinged or jointed bolt pusher consisting of suitable toggle links 39 which 'connect with the bolt carrier 20 and with a spring pressed plunger 40 that rides in a. spring guide 41 in the stock 4 of the gun. This plunger 40 is engaged by a relatively stout coil spring 42 constituting the main spring of the gun and the compreion of which may be adjusted by means of a suitable-nut 43 in the butt of the stock. It is this spring that absorbs the -shock of the recoil upon the firing of the gun, and also actuates the breech bolt upon the release thereof Nby the trigger mechanism whichwill now be referred to in detail.

As will be observed from the drawings, the lower portion of the breech casing 2 is provided with a trigger guard 44 which has pivoted therein a trigger 45 that is placed under the tension of the coiled 'scar spring 46 clearly shown in Fig. 3 of the drawings. This trigger 45 is connected with the sear element 47 by a link 48, and as the trigger 45 is under the tension of the spring 46, it will be apparent that upon rearward finger pressure on the trigger 45, the link 48 `between the trigger and Sear will be pushed forward. The sear 47 is of substantially T-shaped formation, the shankl portion thereof being pivotally connected with the link 48, while thev head thereof is formed at its front end with a hook 49 for temporarily checking a bolt carrier, and the heel portion thereof is provided with a rearwardly placing shoulder 50 for engaging with the cocking shoulder 22 of the bolt carrier.

When the gun is fired, the force of the recoil will carry the locked barrel and breech mechanism backward through to the limit of the breech casing very rapidly, ordinarily before the irer can remove his finger from the trigger. Thus, owing to the hook' and shoulder formation of the scar, the check shoulder 21 ofthe bolt carrier is first engaged with the hook 49 of the sear While the trigger is in retracted condition, that is, before the operator removes his finger therefrom after firing a shot. However, upon removing finger pressure from the trigger, the' sp1-111g 46 pulls'the arm 47 rearwardly and pushes the shoulder 50 up into the path of thecocking shoulder 22 and pulls the' hook 49'out of the path of the shoulder 21. With 'this construction of scar, a. double engagement of the breech mechanism is insured, so that there is no possibility of the bolt carrier movmg forward under the pressure of the spring 42'after it has been driven back to its normal position by the'force of the recoil.

The cartridge magazine M may be inserted in the lower portion or framework of the breech casing 2 in the slot 51, where it is held in place by a suitable spring-pressed latch element 52 to properly feed the cartridges into the feed zone between the breech mechanism and the firing chamber of the gun barrel. The magazine is so constructed as to receive the free end portion 53 of a trigger stop lever 54 which is pivotally mounted on the sear axis 55 and has the rear end 56 pressed upward by a spring 57. This spring 57 holds the end 5G of the trigger guard normally clear of the upper end of the trigger so that the latter will always be operative as long as the. magazine contains more than one cartridge. However, when the'last cartridge is in the feed zone, between the breech mechanism and the barrel, the magazine follower F engages the end 53 of the trigger stop-lever and pushes the same upward, thus pushing the end 56 down against the tension of the flat spring 57 into the path of the upper end of the trigger 45 so that the same cannot be moved a suiiicient distance to operate the sear and thus release the breech mechanism. This construction provides for announcing that the magazine needs refilling and also locks the breech mechanism in cocked position to facilitate the placing of a-full magazine in the gun. i

Fig. 2 of the drawings shows the position of parts when the gun is cocked or ready for firing. As will be observed fro'm this figure, the breech mechanism B, including the breech bolt 25 and bolt carrier 20, are held at the extreme rear end of the breech casing 2, by means of the sear 27 of the trigger mechanism against the tension of the spring 42. The barrel 1 is locked between the guide and abutment member 6 and the spring-pressed detent 14, and a cartridge from the magazine M occupies the feeding zone between the breech mechanism and the firing chamber of the relatively fixed gun barrel 7. Upon pulling the trigger 45 against the tension of the spring 46, the sear 47 is rocked on its axis 55, so that the hook v is released from engagement with the y shoulder 22 on the breech bolt carrier. This latter element, as previously described in the lnormal condition of the' apparatus, has the cartridge positioning breech bolt 25 locked in an extended position as shown in Figs. 2, 5, and 6. Thus, when the'shoulder 50 disengages the shoulder 22, the entire breech mechanism isv rapidly thrust forward by the main spring 42 with the breech bolt in eX- tended position to thereby sweep a cartridge from the feed zone into the firing chamber 8 of the barrel 7.

In the forward flight of the breech mechanism, up to a 'point where the cartridge is finally seated in the cartridge chamber 8 of the gun barrel, the bolt 25 remains locked by the pawl 37 in its extended position. However, at the instant the cartridge is finally seated, or perhaps a fractional period bolt carrier having the firing pin 26 rigid therewith, continues to advance and compel the end 28 of the ring'pin to detonate the cap of the cartridge. In this connection, it will be noted that the slot 30 is provided with a substantially straight portion at its forward end, so that after a quarter turn has been given to the bolt 25 by the pin 31 riding in the curved part of the slot, the final movement of the bolt carrier is in a substantially straight line to thereby thrust the firing pin through the bolt to detonate the cartridge cap.

Simultaneously with the detonation of the cartridge, the fork 23 depresses the detent 14 and unlocks the barrel 7, so that the re-l coil will drive the breech mechanism backward against the absorbing tension o f the main spring 42. At this time, as previously indicated, the rer not having removed his finger from the trigger, the carrier 20 will be engaged and checked by the hook 49 of the sear, but as soon as finger pressure is released from the trigger, the shoulder 50 of the sear will engage with the cocking shoulder 22 of the bolt carrier. When the recoil takes place, it will be clear that both the barrel and breech mechanism, being interlocked by the lugs 10 and projections 32, the bolt 25 will remain fully housed within the socket 24 as shown in Fig. 3. That is to say, since the recoil forces both the barrel and breech bolt to therear of the casing in a locked condition, it will be clear that the locking projections on the breech bolt 25 will be in a horizontal position and engaged behind the inturned holding lugs 10. However, as soon as the sear preliminarily en-v gages the bolt carrier at 21, the barrel will be pulled forward by means of the barrel retracting spring 13, whereupon the barrel automatically becomes disengaged from the bolt by the turning of the latter due to the provision of the slot 30 and pin 31. When the barrel 7 starts its forward return movement, the end 36 of the pawl 37 rests idly on the surface of the bolt 25. Therefore, the bolt is free to rotate a quarter turn when pulled by the barrel to bring the projections 32 from their horizontal position behind the lugs 10 to a vertical position to clearv the same, and thereby permit the barrel to return unhindered to its position behind the lug 14, and at the same time pulling the bolt 25 out of the socket 24-in the carrier to the position as shown in Figs. 2, 5, and 6.

It will, of course, be apparent that when the locln'ng end 36 thereof rides on the periphery of the bolt 25 as above indicated until the bolt is pulled to its outward limit from the socket 24, at which time the said end 36 will engage with the transverse recess 35 and again hold the bolt locked in its extended position.

The forward movement of the barrel permits the ejection of the fired' cartridge through the opening 17 in the top of' the breech casing and permits a fresh cartridge to come into the feed zone, and when the barrel has reached its forward limit under the influence of the spring 13, it again be-n comes engaged behind the detent 14, and thereby assumesla relatively locked position.

A further novel feature of the invention resides in the provision of a detachable breech-bolt knob designated generally as 58. This knob essentially comprises Va body 59 having a bolt carrier engaging foot portion 60 which is substantially of T-shape in cross section, and a spring-pressed locking lug 61 which is controlled through an exposed finger button 62. This knob may be inserted in a longitudinal slot 63 in the side of the breech casin 2 as shown in Fig. 4 of the drawings andl 64 of the bolt carrier 20 whereby lthe lug 61 will snap into the locking hole 61a and hold the knob locked to the carrier. When the knob is thus held to the carrier it is guarded in the slot 63 to compel the breech bolt to move in a rectilinear path in the breech casing. That is to say, the detachable knob 58 acts as a sliding element to compel the breech bolt to move rectilinearlyv and prevents the rotation thereof, and atthe same time con- VStitutes a detachable retaining element for holding the breech bolt in place in the breech casing. Owing to its construction, the lmob may be readily removed to take the gun apart. Furthermore, in case the gun becomes jammed, or the main spring temporarily refuses to work, this knob being exposed through the casing constitutes a convenient means for operating the breech bolt by hand.

Themagazine M shown in the drawings is only one form of magazine that may be utilized in connection with the present firearm, since the improved mechanism vdescribed in the foregoing specification is intended to be available for use with any type of magazine that may be itteitl to the gun.

Furthermore, any conventional ejector means may be employed for removing the empty shells from the feed zone between the breech bolt and-firing chamber of the gun barrel.

Without further description, it is thought that the many features and advantages of the present' invention will be readily apparent, and it will, of course, be understood,`

that various changes in the form, proport1on,-aiid minor details of construction may then inserted in the T socketv spirit of the invention or scope of the appended claims.

I claim:

1. In an automatic firearm, a recoil-operated barrel, a spring actuated breech-bolt device including a tubular bolt carrier, a iring pin coaxially arranged within the carrier and rigidly connected at one end thereto, a cartridge positioning bolt slidably mounted in the bolt carrier and slidable upon the firing pin, and an automatic device for temporarily locking the bolt to the carrier, and means for automatically locking the bolt to the barrel and releasing it therefrom.

2. An automatic iirearm including a recoil operated barrel, locking means for holding said barrel in a relatively fixed position, a spring actuated breech bolt having means for placing a cartridge in the barrel and also having means for releasing said locking means to permit the recoil of the barrel, and

a trigger device having means engaging and releasing the breech bolt. v 3. An automatic firearm including a spring tensioned barrel, locking meansv for holding the barrel in firing position, a spring actuated breech bolt having cartridge positioning means, and also having means for releasing said locking means to permit recoil of the barrel, holding lugs carried by the rear end of the barrel adapted to automatically engage said cartridge positioning means, and a trigger device for engaging and releasing the breech bolt.

4. An automatic firearm including a tubular casing, a riie barrel in the casing, means for holding the barrel in firing position, a spring actuated breech bolt slidable in the casing, means for automatically locking saidI ing, said device including abolt carrier having means for automatically releasing said barrel locking detent, a rectilinearly and rotatably movable breech-bolt having a' locking engagement with the barrel, and means f or locking the-breech-bolt in an extended position, and a trigger device for engaging and releasing said breech-bolt device.

6. An automatic firearm including a tubular casing, a rifle barrel in the casing, inturned holding lugs at the loading kend of said barrel, a spring for positionin the barrel in the casing, a spring pressed etent for engaging the loading end of the barrel to hold the same in firing position, a spring actuated breech bolt device includinga bolt carrier having means for engaging said isa spring pressed detent to release the barrel, and also havin a rectilinearly and rotatably movable breec bolt having means for en gaging with said holding lugs on the end of the barrel, a firing pin carried by the bolt carrier and projecting axially through the bolt, means for engaging and releasing the breech bolt to permit movement thereof, and a trigger device for engaging and releasing the carrier of the breechbolt device.

7. In an automatic firearm, a tubular casing, a riie barrel in the casing, inturned holding lugs carried by the loading end of said barrel, a spring for positioning the barrel within the casing, a spring-pressed detent for engaging the loading end of the barrel to hold the same in firing position, a spring actuated breech bolt device including a bolt carrier having means for engaging said spring pressed detent to release the barrel, said breech bolt device also including a movable breech bolt having oppositely disposed locking projections for engaging said holding lugs at the end of the barrel, a firing pin carried by the bolt carrier and projecting axially through the bolt, a spring pressed pawl carried by the bolt carrier for locking the said movable bolt in extended position, a cam carried by said casing for engaging with said paWl to release said bolt, and a trigger device for engaging and releasing the carrier of the breech bolt device.

8. In an automatic firearm, a tubular casing, a riie barrel therein, inturned holding lugs carried by the loading end of said barrel, a barrel retracting spring, a springpressed detent for holding the barrel in liring position, a spring actuated breech bolt device including a ,bolt carrier having means for engaging said spring pressed detent, and also having a socket, a breech bolt fitting in said socket and having a spiral slot in its periphery, a pin projecting through the body of said carrier and fitting in said slot, said breech bolt also having oppositely disposed locking projections for engaging said holding lugs at the end of the barrel, a fir- 1ng pin carried by lthe bolt carrier and projecting axially through the bolt, means for locking said bolt in extended position, a cam carried by said casing for engaging said means to release the bolt, and a trigger device or engaging and releasing the carrier of the breech bolt device.

9. An automatic firearm including a recoil operated barrel, a spring-proj-ected breech bolt device having a releasable interlocking connection With the barrel and provided With spaced shoulders, a rocking sear having separate elements respectively engaging said 'spaced shoulders of the breech bolt device, and a spring-retracted trigger having an operating connection with the sear.

10. An automatic lirearm including a recoil operated barrel, a spring projected breech bolt having a releasable interlocking connection with the barrel and provided With a shoulder located adjacent each end thereof, a rocking sear having separate elements respectively engaging said shoulders of the breech bolt, and a spring retracted trigger member having a link connection with the sear.

11. An automatic irearm including a recoil operated barrel, a spring projected breech bolt having a releasable interlocking connection with the barrel and provided with a check shoulder locatedgadjacent its front end and a cooking shoulder located adjacent its rear end, a rocking sea-r having separate elements for respectively engaging said check and cooking shoulders of the breech bolt, and a spring-retracted trigger member having a link connection With the sear.

12. An automatic firearm including a vrecoil operated barrel, a Ispring projected breech bolt having a releasable interlocking connection With the barrel and provided with spaced shoulders, `a rocking Sear having double means for engaging saidshoulders in successive order, and a spring retracted trigger member having an operative connection With the sear.

13. In an automatic firearm, the combination with a breech mechanism and a sliding gun barrel, of a clip fitted to the barrel and having a hinged attaching member inter-A OLIVER BERRY SAALFIELD.

Witnesses:

LAD-RANCE ANGEL, CEAS. E. WAL'roN. 

